[llvm-commits] Add scope info in DebugLoc

[Chris Lattner]

> IR support would be ideal. Will it support line info as well ?

The goal is to move DebugLoc into the Instruction class (like it is in  
MachineInstr), and encode into the 32-bit cookie information about  
line numbers and scopes (regionstart/end info).  This information  
should include inline function information as well.  The thought is  
that this will make the debug information much easier to reconstruct  
in the front-end and also makes it easy to preserve through the  
optimizer.  The outstanding question is how to encode debugloc in 32- 
bit and retain this information.  Something like the clang  
SourceLocation approach should work, though I haven't had time to  
think much about it.

On May 8, 2009, at 12:20 PM, Stefanus Du Toit wrote:
> On 8-May-09, at 1:25 PM, Evan Cheng wrote:
>> Eventually we'd like to move scoping information to the llvm IR  
>> level.
>> But this seems like a good interim step. Bill can you review this  
>> when
>> you have some time?
>
> Just curious, is this purely for debugging/profiling, or do you intend
> to use scope information to assist optimizations in some way?

This is metadata, so it should only be used for debug info,  
diagnostics, etc.  I'm also interested in adding explicit intrinsics  
for "this memory location is dead/live here" but that will be an  
explicit thing in the IR.

-Chris